Piot incapacitation.  

Depends a lot on aircraft, any aircraft without an autopilot or basic SAS if I go unconscious its a lawn dart in seconds.  On our EC135 we have at least shown them to engage heading/ALT hold, make sure collective is at 8 on the FLI and then use the SAT phone to call dispatch.  The goal being someone gets the call patched to another company pilot who can help them down by loading and having the autopilot fly an ILS/LPV approach.  When the aircraft switches to ALT hold at the runway, lower the collective and as the aircraft starts to slow it will eventually fall through 65', as ground contact is about to occur switch both engine to off and hold on.  Probably going to slide off the runway and roll over and be a very dramatic crash but there is a chance you might live......maybe....

Thats about all you can hope for but I tell them if I go you are pretty much done for.  Autopilot is always on for me once above 60kts and I only kick it off 2 miles out so odd are if I go unconscious the autopilot is already on.